From 0ec13aff058a82426c8d44b688c804cc4a5a0a3d Mon Sep 17 00:00:00 2001
From: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Date: Wed, 23 Jun 2021 21:13:10 -0700
Subject: [PATCH] Revert "ibmvnic: simplify reset_long_term_buff function"

References: bsc#1186206 ltc#191041
Patch-mainline: v5.14-rc1
Git-commit: 0ec13aff058a82426c8d44b688c804cc4a5a0a3d

This reverts commit 1c7d45e7b2c29080bf6c8cd0e213cc3cbb62a054.

We tried to optimize the number of hcalls we send and skipped sending
the REQUEST_MAP calls for some maps. However during resets, we need to
resend all the maps to the VIOS since the VIOS does not remember the
old values. In fact we may have failed over to a new VIOS which will
not have any of the mappings.

When we send packets with map ids the VIOS does not know about, it
triggers a FATAL reset. While the client does recover from the FATAL
error reset, we are seeing a large number of such resets. Handling
FATAL resets is lot more unnecessary work than issuing a few more
hcalls so revert the commit and resend the maps to the VIOS.

Fixes: 1c7d45e7b2c ("ibmvnic: simplify reset_long_term_buff function")
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
 drivers/net/ethernet/ibm/ibmvnic.c | 46 ++++++++++++++++++++++++------
 1 file changed, 38 insertions(+), 8 deletions(-)

diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index 5788bb956d73..4b4eccc496a8 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c
@@ -257,12 +257,40 @@ static void free_long_term_buff(struct ibmvnic_adapter *adapter,
 	dma_free_coherent(dev, ltb->size, ltb->buff, ltb->addr);
 }
 
-static int reset_long_term_buff(struct ibmvnic_long_term_buff *ltb)
+static int reset_long_term_buff(struct ibmvnic_adapter *adapter,
+				struct ibmvnic_long_term_buff *ltb)
 {
-	if (!ltb->buff)
-		return -EINVAL;
+	struct device *dev = &adapter->vdev->dev;
+	int rc;
 
 	memset(ltb->buff, 0, ltb->size);
+
+	mutex_lock(&adapter->fw_lock);
+	adapter->fw_done_rc = 0;
+
+	reinit_completion(&adapter->fw_done);
+	rc = send_request_map(adapter, ltb->addr, ltb->size, ltb->map_id);
+	if (rc) {
+		mutex_unlock(&adapter->fw_lock);
+		return rc;
+	}
+
+	rc = ibmvnic_wait_for_completion(adapter, &adapter->fw_done, 10000);
+	if (rc) {
+		dev_info(dev,
+			 "Reset failed, long term map request timed out or aborted\n");
+		mutex_unlock(&adapter->fw_lock);
+		return rc;
+	}
+
+	if (adapter->fw_done_rc) {
+		dev_info(dev,
+			 "Reset failed, attempting to free and reallocate buffer\n");
+		free_long_term_buff(adapter, ltb);
+		mutex_unlock(&adapter->fw_lock);
+		return alloc_long_term_buff(adapter, ltb, ltb->size);
+	}
+	mutex_unlock(&adapter->fw_lock);
 	return 0;
 }
 
@@ -484,7 +512,8 @@ static int reset_rx_pools(struct ibmvnic_adapter *adapter)
 						  rx_pool->size *
 						  rx_pool->buff_size);
 		} else {
-			rc = reset_long_term_buff(&rx_pool->long_term_buff);
+			rc = reset_long_term_buff(adapter,
+						  &rx_pool->long_term_buff);
 		}
 
 		if (rc)
@@ -607,11 +636,12 @@ static int init_rx_pools(struct net_device *netdev)
 	return 0;
 }
 
-static int reset_one_tx_pool(struct ibmvnic_tx_pool *tx_pool)
+static int reset_one_tx_pool(struct ibmvnic_adapter *adapter,
+			     struct ibmvnic_tx_pool *tx_pool)
 {
 	int rc, i;
 
-	rc = reset_long_term_buff(&tx_pool->long_term_buff);
+	rc = reset_long_term_buff(adapter, &tx_pool->long_term_buff);
 	if (rc)
 		return rc;
 
@@ -638,10 +668,10 @@ static int reset_tx_pools(struct ibmvnic_adapter *adapter)
 
 	tx_scrqs = adapter->num_active_tx_pools;
 	for (i = 0; i < tx_scrqs; i++) {
-		rc = reset_one_tx_pool(&adapter->tso_pool[i]);
+		rc = reset_one_tx_pool(adapter, &adapter->tso_pool[i]);
 		if (rc)
 			return rc;
-		rc = reset_one_tx_pool(&adapter->tx_pool[i]);
+		rc = reset_one_tx_pool(adapter, &adapter->tx_pool[i]);
 		if (rc)
 			return rc;
 	}
-- 
2.26.2